Conventionally, ceramic electronic components using a ferrite-based magnetic substance which has a spinel type crystal structure, such as Ni—Zn, have been widely used, and active development of ferrite materials has occurred.
For example, Patent Document 1 proposes a ferrite element with an integrally fired copper conductor, in which the raw material composition of the ferrite matrix has a PbO constituent added at a ratio of 0.3 parts by weight or more and 5.0 parts by weight or less with respect to 100 parts by weight of Ni—Zn based ferrite.
Furthermore, Patent Document 1 proposes a ferrite element with an integrally fired copper conductor, in which the raw material composition of the ferrite matrix has a PbO constituent present at an amount of 0.3 parts by weight or more and 5.0 parts by weight or less, a B2O3 constituent at an amount of 0.03 parts by weight or more and 1.5 parts by weight or less, and a SiO2 constituent at an amount of 0.03 parts by weight or more and 1.5 parts by weight or less, with respect to 100 parts by weight of Ni—Zn based ferrite.
In Patent Document 1, the addition of PbO, or of PbO, B2O3, and SiO2 as a low-melting-point glass constituent to the ferrite material allows firing at low temperatures of 950 to 1,030° C. in a nitrogen atmosphere.
In addition, Patent Document 2 proposes an oxide ceramic material composed of a sintered body which has a composition containing 0.1 to 0.5 wt % of Mn2O3 as an accessory constituent with respect to a main constituent composed of 44 to 47 mol % of Fe2O3, 5 to 13 mol % of CuO, and 15 to 23 mol % of ZnO with the rest substantially composed of NiO, and has an average crystal grain size of 0.7 to 1.2 μm.
In Patent Document 2, the specific resistance ρ is improved by containing 0.1 to 0.5 wt % of Mn2O3 while a paste of internal electrodes and a paste for oxide magnetic layers are subjected co-firing by the use of Ag in an internal electrode material, thereby achieving a laminate-type inductor which has a favorable quality factor Q and excellent direct-current bias characteristics, without decreasing the sintered density.
In addition, Patent Document 2 discloses that it is also possible to use a Cu-based material as the internal electrode material.
Patent Document 1: Japanese Examined Patent Application No. 7-97525 (claim 1, claim 2, lines 7-8 in column 5 of page 3)
Patent Document 2: Japanese Patent Application Laid-Open No. 2006-219306 (claim 1, paragraph numbers [0013], [0019], [0035])